SKM SK Telecom Co Ltd

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

FOR THE MONTH OF June 2024

COMMISSION FILE NUMBER: 333-04906

SK Telecom Co., Ltd.

(Translation of registrant’s name into English)

65, Eulji-ro, Jung-gu

Seoul 04539, Korea

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒     Form 40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a Form 6-K if submitted solely to provide an attached annual report to security holders.

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a Form 6-K if submission to furnish a report or other document that the registration foreign private issuer must furnish and make public under the laws of the jurisdiction in which the registrant is incorporated, domiciled or legally organized (the registrant’s “home country”), or under the rules of the home country exchange on which the registrant’s securities are traded, as long as the report or other document is not a press release, is not required to be and has not been distributed to the registrant’s security holders, and if discussing a material event, has already been the subject of a Form 6-K submission or other Commission filing on EDGAR.

QUARTERLY BUSINESS REPORT

(From January 1, 2024 to March 31, 2024)

THIS IS A SUMMARY OF THE QUARTERLY BUSINESS REPORT ORIGINALLY PREPARED IN KOREAN WHICH IS IN SUCH FORM AS REQUIRED BY THE KOREAN FINANCIAL SERVICES COMMISSION.

IN THE TRANSLATION PROCESS, SOME PARTS OF THE REPORT WERE REFORMATTED, REARRANGED OR SUMMARIZED FOR THE CONVENIENCE OF READERS.

ALL REFERENCES TO THE “COMPANY” SHALL MEAN SK TELECOM CO., LTD. AND, UNLESS THE CONTEXT OTHERWISE REQUIRES, ITS CONSOLIDATED SUBSIDIARIES. REFERENCES TO “SK TELECOM” SHALL MEAN SK TELECOM CO., LTD., BUT SHALL NOT INCLUDE ITS CONSOLIDATED SUBSIDIARIES.

UNLESS EXPRESSLY STATED OTHERWISE, ALL INFORMATION CONTAINED HEREIN IS PRESENTED ON A CONSOLIDATED BASIS IN ACCORDANCE WITH THE INTERNATIONAL FINANCIAL REPORTING STANDARDS ADOPTED FOR USE IN KOREA (“K-IFRS”) WHICH DIFFER IN CERTAIN RESPECTS FROM GENERALLY ACCEPTED ACCOUNTING PRINCIPLES IN CERTAIN OTHER COUNTRIES, INCLUDING THE UNITED STATES. THE COMPANY HAS MADE NO ATTEMPT TO IDENTIFY OR QUANTIFY THE IMPACT OF THESE DIFFERENCES.

Omitted in quarterly reports in accordance with applicable Korean disclosure rules. For more information, please refer to the Company’s annual business report for the year ended December 31, 2023.

1. Business Overview

Each company in the consolidated entity is a separate legal entity providing independent services and products. The Company’s business is primarily separated into (1) the wireless business consisting of cellular voice, wireless data and wireless Internet services, (2) the fixed-line business consisting of fixed-line telephone, high-speed Internet, data and network lease services, among others and (3) other businesses consisting of commercial retail data broadcasting channel business, among others.

Set forth below is a summary description of the business of each of the Company’s material consolidated subsidiaries.

[Wireless Business]

Wireless telecommunications companies provide services based on competitive strengths in handheld devices, affordable pricing, network coverage and an extensive contents library. The Company continues to maintain its reputation as the unparalleled premium network operator in the 3G, 4G and 5G markets on the basis of its technological leadership and network management technology. With the world’s first commercialization of 5G technology in 2019, the Company continues to maintain its position as the top network operator in the 5G era and strives to provide differentiated services to its customers.

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In order to strengthen its sales channels, the Company has been offering a variety of fixed-line and wireless telecommunications convergence products through its subsidiary, PS&Marketing. PS&Marketing provides differentiated service to customers through the establishment of new sales channels and product development. Through its subsidiary Service Ace, the Company operates customer service centers and provides telemarketing services. Additionally, SK O&S, the Company’s subsidiary responsible for the operation of the Company’s networks, provides customers with quality network services and provides the Company with technological know-how in network operations.

The Company has been maintaining solid profitability based on the stable sales generated from its 5G subscribers, together with efficient investments in, and operation of, its wireless networks and stabilization of market competition. The Company’s 5G wireless services, which recorded 15.93 million subscribers as of March 31, 2024, accounted for 70% of the Company’s total number of subscribers. The Company continually seeks growth in the number of its 5G wireless subscribers while actively implementing artificial intelligence (“AI”) technology into its fixed-line and wireless businesses, thereby continuing efforts to optimize efficiencies in operational and capital expenditures.

In addition, the Company has been promoting growth in its enterprise business by developing various AI-related business items, including AI contact centers, vision AI and big data, while continuing efforts to increase demand for the Company’s Internet of Things (“IoT”) lines. For the three months ended March 31, 2024, the Company’s enterprise business recorded an increase in revenue of approximately 10% compared to the three months ended March 31, 2023. In particular, based mainly on recurring revenue, the Company’s cloud business recorded an increase in revenue of approximately 40% for the three months ended March 31, 2024 compared to the three months ended March 31, 2023, thereby driving the revenue growth of the Company’s overall enterprise business.

“A. (Adot),” the Company’s Korean language GPT-3 based service, has resonated with the market by introducing call recording and summarization features, and it continues to innovate customers’ communication experience, including by introducing real-time interpretation service during calls. In April 2024, the Company expanded A.’s call recording and summarization features as well as real-time interpretation service during calls, which have been highly popular among iPhone users, to devices run on the Google Android operating system.

The telecommunications services market can be categorized into telecommunications services (such as fixed-line, wireless and leased line services, as well as sales intermediary services relating thereto and value-added services) and broadcasting and telecommunications convergence services (including IPTV and integrated fixed-line and mobile telecommunications services). Pursuant to the Telecommunications Business Act, the telecommunications services market can be further classified into basic telecommunications (fixed-line and wireless telecommunications), special category telecommunications (resale of telecommunications equipment, facilities and services) and value-added telecommunications (Internet connection and management, media contents and others).

The size of the domestic telecommunications services market is determined based on various factors specific to Korea, including the size of the population that uses telecommunications services and telecommunications expenditures per capita. While it is possible for Korean telecommunications service providers to provide services abroad through acquisitions or otherwise, foreign telecommunications services markets have their own characteristics depending, among others, on the regulatory environment and demand for telecommunications services.

The Korean mobile communications market is considered to have reached its maturation stage with more than a 100% penetration rate. However, the Korean mobile communications market continues to improve in the quality of services with the help of advances in network-related technology and the development of highly advanced smartphones which enable the provision of new ICT services for advanced multimedia contents, mobile commerce, mobility and other related services. In addition, the ultra-low latency and high capacity characteristics of 5G networks as well as the advancement of AI are expected to accelerate the introduction of new services and the growth of IoT-based B2B businesses.

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The Korean mobile communications market includes the entire population of Korea with mobile communications service needs, and almost every Korean is considered a potential user. Sales revenue related to data services has been growing due to the increasing popularity of smartphones and high-speed wireless networks. There is also a growing importance of the B2B segment, which creates added value by selling and developing various solutions. The telecommunications industry is a regulated industry requiring license and approval from the MSIT.

In the wireless business, industry players compete on the basis of the following three main competitive elements:

(i) brand competitiveness, which refers to the overall sense of recognition and loyalty experienced by customers with respect to services and values provided by a company, including the images created by a company’s comprehensive activities and communications on top of the actual services rendered;

(ii) product and service competitiveness, which refers to the fundamental criteria for wireless telecommunications services, including voice quality, service coverage, broad ranges of rate plans, diversified mobile Internet services, price and quality of devices, and customer service quality, as well as the ability to develop new services that meet customer needs in a market environment defined by convergence; and

(iii) sales competitiveness, which refers to novel and diversified marketing methods and the strength of the distribution network.

Set forth below is the historical market share of the Company (excluding MVNO subscribers).

In 2021, the Company successfully completed the Spin-off of SK Square Co., Ltd. from SK Telecom (the “Spin-off”) in order to maximize shareholder value. In the same year, the Company also unveiled its “SKT 2.0” vision to pursue the maximization of its overall enterprise value centered around five major business areas. In November 2022, the Company announced its differentiated “AI Company” vision to further organize and clarify the direction of SKT 2.0 and combine AI with connectivity technologies based on its main telecommunications business. In September 2023, as part of the Company’s effort to transform into a “global AI company,” the Company announced its new “AI Pyramid” strategy, which aims to bring innovation across various industrial and lifestyle areas centered around three key aspects. The AI Pyramid strategy is in the form of a pyramid and integrates a “self-reinforcement model,” which seeks to strengthen the Company’s relationship with its customers through advances in the Company’s AI technology and the creation of AI services, with a “cooperation model,” which focuses on AI-related alliances. Through these initiatives, the Company is striving to transform into a global AI company.

For the three months ended March 31, 2024, the Company recorded Won 4.47 trillion in operating revenue and Won 0.50 trillion in operating profit on a consolidated basis. The increased competitiveness of telecommunications services and the rapid progress in new growth businesses such as B2B have enabled the Company to continue to improve its operating results.

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SK Telink, a consolidated subsidiary of the Company, operates its MVNO service, “SK 7Mobile,” which is offered at reasonable rates and provides excellent quality. SK Telink is increasing its efforts to develop low-cost distribution channels and create niche markets through targeted marketing towards customers including foreign workers, middle-aged adults and students.

SK O&S, a subsidiary of the Company responsible for the operation of the Company’s base stations and related transmission and power facilities, offers quality fixed-line and wireless network services to customers, including mobile office products to business customers. In addition, Service Ace is developing its competence as a marketing company while providing top-quality customer service.

PS&Marketing, a subsidiary of the Company, provides a sales platform for products of the Company and SK Broadband including fixed-line and wireless telecommunications products that address customers’ needs for various convergence products. PS&Marketing provides differentiated service to clients through the establishment of new sales channels and product development.

[Fixed-line Business]

For the three months ended March 31, 2024, SK Broadband recorded Won 1.09 trillion in revenue on a consolidated basis, which represented a 2.7% increase from Won 1.06 trillion for the three months ended March 31, 2023. Such increase was primarily attributable to the growth of SK Broadband’s media business resulting from an increase in the number of subscribers and the growth of its B2B business primarily focused on new data centers.

SK Broadband’s business is divided into the media business segment, which provides IPTV and cable TV services, and the fixed-line business segment, which provides high-speed Internet, telecommunications, leased lines and data center services.

For the three months ended March 31, 2024, the media business segment recorded Won 0.48 trillion in revenue, which represented a 0.9% increase compared to the three months ended March 31, 2023. For the three months ended March 31, 2024, the fixed-line business segment recorded Won 0.61 trillion in revenue, which represented a 4.3% increase compared to the three months ended March 31, 2023.

The domestic telecommunications service industry displays the typical characteristics of a domestic industry given that its coverage area is limited to Korea. As a result, the size of the industry is greatly affected by the domestic economic factors including the domestic user population and the level of telecommunications service expenditures in light of the domestic income level. Domestic telecommunications companies may expand overseas through acquisitions or direct expansion, but the overseas telecommunications service industries are subject to inherently different industry characteristics from the domestic one, depending on the regulatory and demand characteristics of each country.

The broadcasting business involves the planning, programming or production of broadcasting programs and transmission to viewers through telecommunications facilities. The broadcasting market can be categorized into terrestrial broadcasting, fixed-line TV broadcasting, satellite broadcasting and programming-providing businesses, in each case pursuant to the Broadcasting Act, as well as Internet multimedia broadcasting business pursuant to the Internet Multimedia Broadcast Services Act. The Company engages in the fixed-line TV broadcasting business, which is defined as the business of managing and operating fixed-line TV broadcasting stations (including their facilities and employees for the purpose of providing multi-channel broadcasting) and providing broadcasts through transmission and line facilities. The Internet multimedia broadcasting refers to the broadcasting of programs through a combination of various contents including data, video, voice, sound and/or e-commerce, including real-time broadcasting, while guaranteeing a consistent service quality through a bidirectional Internet protocol using a broadband integrated information network.

As a result of the government’s direct and indirect control over the fixed-line telecommunications industry, ranging from service licensing to business activities, the industry’s overall growth potential and degree of competition are greatly affected by the government’s regulatory policies. The fixed-line telecommunications industry is also a technology-intensive industry that evolves rapidly and continuously through the development of communications technology and equipment, which requires proactive responses in meeting the needs of subscribers by developing new services and penetrating the market. Fixed-line telecommunications services have become universal and essential means of communication and act as the foundation for integration and convergence with various other services. The essential nature of such services provides stable demand, resulting in low sensitivity to economic conditions.

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In addition, the Korean fixed-line services industry is marked by a high level of market concentration, as the government is highly selective in granting telecommunications business licenses. While the competitive landscape of the fixed-line and wireless services markets is dominated by its three leading operators, the Company (including SK Broadband), KT and LG U+, the intensity of competition is growing as digitalization of communication technologies and devices leads to the convergence of fixed-line and wireless services, as well as broadcasting and telecommunications, and technology for faster data communications services is developed.

In the high-speed Internet services market, the demand for Giga Internet services has been continuing to increase due to the popularization of mobile and home IoT devices and the expansion of large media services including video streaming services.

In the paid broadcasting market, competition for content has been intensifying, at the center of which are large over-the-top operators with strength in exclusive content. Reflecting a rapid change in content consumption patterns and behaviors of viewers, the Company is preparing for new growth in the home platform domain by providing customized services using ICT convergence technologies such as AI and big data in addition to differentiated contents.

In the corporate business market, the Company expects to see growth in new business areas, following the emergence of new services including AI. The Company is continuing its efforts to generate stable returns by strengthening its competitiveness in the traditional fixed line-based business through expansion of core infrastructure including data centers and leased lines, for which market demand has been continually growing.

High-speed Internet and fixed-line telephone services operate in mature markets that are comparatively less sensitive to cyclical economic changes as the services provided by different operators have become less differentiated. TV services have become necessities that provide broadcasting, and the market, which is subject to a subscriber-based business model, has little sensitivity to cyclical economic changes.

Set forth below is the historical market share of the Company.

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The Company is engaged in a number of business areas including high-speed Internet, home telephone, corporate business, IPTV and cable TV pursuant to the relevant communications regulations such as the Telecommunications Business Act, the Internet Multimedia Broadcast Services Act and the Broadcasting Act. In each of its principal business areas, the Company competes on the basis of price, service quality and speed. In the IPTV business, the ability to offer complex services and differentiated contents are becoming increasingly important. General telecommunications businesses operate in a licensed industry with a high barrier of entry, which is dominated by the Company, KT and LG U+.

[Other Businesses]

The commercial retail data broadcasting channel business of SK Stoa offers an interactive service that integrates television home shopping and data home shopping services. Such integrated service allows television viewers to organize various product categories on the television screen and select and purchase desired products using a television remote control or mobile device, unlike traditional home shopping services that only allowed for real-time purchase through the relevant broadcast.

Sapeon, an AI semiconductor company, launched “X330,” its next-generation inference AI chip, and plans to further utilize its AI semiconductor capabilities and operational know-how in its efforts to lead the global market in next-generation AI data centers.

2. Key Financial Data by Business Line

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3. Updates on Major Products and Services

4. Price Trends for Major Products

[Wireless Business]

As of March 31, 2024, based on the Company’s standard monthly subscription plan, the basic service fee was Won 12,100 (including value-added tax) and the usage fee was Won 1.98 per second. Among the 4G-based plans, the “T-Plan Safe 4G” provides 4 GB of data and unlimited voice calls at Won 50,000 per month (including value-added tax). Among the 5G-based plans, the “Basic” plan provides 11 GB of data and unlimited voice calls at Won 49,000 per month (including value-added tax). On June 1, 2023, the Company launched the “5G 0 Youth” plan, which actively reflects the data usage patterns and lifestyle trends of the younger demographics. The Company plans to continue to introduce new services that reach out to different customer segments. The Company provides a variety of other subscription plans catering to subscriber demand, which may be reviewed on the Company’s website at www.tworld.co.kr.

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[Fixed-line Business]

On March 2, 2024, SK Broadband launched the “2030 Direct” plan, which is aimed at cost-conscious customers in their 20s and 30s who feel uncomfortable with entering into long-term subscription plans. Such plan offers Internet services under a one-year subscription plan at a rate comparable to that of a three-year contract. Customers between the age of 18 and 39 who sign up for this plan through SK Broadband’s website, B Direct Shop, or call center, 106 Customer Center, are eligible for a one-year Internet service contract including Wi-Fi at a rate that provides a discount of up to 55% compared to the rate for a non-term contract internet service.

In addition, on March 11, 2024, SK Broadband launched the “Budget-friendly Combination” plan, which offers a discount when bundling SK Broadband’s fixed-line services (Internet and IPTV) and the wireless services of certain MVNOs that lease SK Telecom’s network (including Liiv M Mobile, Eyagi Mobile, Mobing, Toss Mobile and Eyes mobile). This plan provides benefits equivalent to that of the “Modern Family Combination” plan, which bundles SK Broadband’s fixed-line services and SK Telecom’s wireless services. Based on a three-year contract, the plan offers discounts up to Won 14,300, including a Won 13,200 discount on high-speed Internet service fees and a Won 1,100 discount on IPTV fees (when bundled with IPTV services). However, no discounts are offered on the MVNO service fees. SK Broadband plans to further expand the list of MVNOs that can be bundled with the Budget-friendly Combination plan. SK Broadband also provides a variety of other subscription plans based on consumer demand, which may be reviewed on the Company’s website at www.bworld.co.kr.

5. Investment Status

[Wireless Business]

[Fixed-line Business]

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6. Revenues

7. Derivative Transactions

Currency and interest rate swap contracts under cash flow hedge accounting as of March 31, 2024 are as follows:

[SK Telecom]

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[SK Broadband]

8. Major Contracts

None.

9. R&D Investments

Set forth below are the Company’s R&D expenditures.

10. Other information relating to investment decisions

The Company manages its corporate brand and other product brands in a comprehensive way to protect and increase their value. The Company operates an intranet system called “Comm.ON” in order to implement consistent communication with consumers across various areas including branding, design, marketing and public relations, and systematically manages the development, registration and licensing of brands through such system.

[SK Telecom]

As of March 31, 2024, the registered patents and trademarks held by the Company included 3,277 Korean-registered patents, 1,769 foreign-registered patents and 725 Korean-registered trademarks. The number of registered patents and trademarks is subject to constant change due to the acquisition of new rights, expiration of terms, abandonments and dispositions.

[SK Broadband]

As of March 31, 2024, SK Broadband held 262 Korean-registered patents and 70 foreign-registered patents (including those held jointly with other companies). It also holds 302 Korean-registered trademarks. SK Broadband owns intellectual property rights to its proprietary graphic design of the alphabet “B” representing its brand. The designed alphabet “B” is registered in all business categories for trademarks (total of 45). The number of registered patents and trademarks is subject to continual change due to the acquisition of new rights, expiration of terms, abandonments and dispositions.

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[SK Telecom]

The Company does not directly engage in any manufacturing and therefore does not undertake any industrial processes that emit pollutants into the air or industrial processes in which hazardous materials are used. Nevertheless, the Company clearly recognizes the severity of the climate crisis and has been diligently fulfilling its social obligations by establishing a systematic and practical environmental management strategy system. Under the vision of “realizing a sustainable future based on ICT” and to achieve Net Zero by 2050, the Company is making efforts to (1) preemptively respond to climate change, (2) improve its environmental management system and (3) create an eco-friendly green culture. To this end, the Company was one of the first information technology companies in Korea to join the RE100 (Renewable Electricity 100%) initiative and signed a green premium contract with Korea Electric Power Corporation. The Company has been implementing company-wide adoption of renewable energy through efforts such as installing solar power generation equipment in its office buildings and base stations. In addition, the Company leads in energy savings and environmental protections based on ICT technology, and recently became the first company in the telecommunications industry to obtain carbon emission rights by reducing greenhouse gas through integration of telecommunications equipment and technology upgrades.

[SK Broadband]

SK Broadband does not directly engage in any manufacturing processes that emit environmental pollutants, and more than 99% of its greenhouse gas emissions is indirect emissions from its use of external electricity. SK Broadband was selected as a business subject to allocation of emission permits as part of Korea’s greenhouse gas emissions trading scheme that commenced in 2015, and it actively fulfills its obligations and consistently achieves the targets set by the government.

In 2021, SK Broadband declared its goal to achieve Net Zero by 2045 in an effort to actively participate in the international community’s response to climate change. Prior to the declaration, SK Broadband had already subscribed to the RE100 initiative in 2020. Since 2021, SK Broadband has participated in Korea Electrical Power Corporation’s renewable energy power purchase program, “Green Premium,” to purchase renewable energy and has installed additional solar power generation facilities to increase the self-production and use of renewable energy.

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1. Summary Financial Information (Consolidated and Separate)

Below is the summary consolidated financial information of the Company as of March 31, 2024, December 31, 2023 and December 31, 2022 and for the three months ended March 31, 2024 and for the years ended December 31, 2023 and 2022. The Company’s consolidated financial statements as of March 31, 2024 and December 31, 2023 and for the three months ended March 31, 2024 and 2023, which are prepared in accordance with K-IFRS, are attached hereto.

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Below is the summary separate financial information of the Company as of March 31, 2024, December 31, 2023 and December 31, 2022 and for the three months ended March 31, 2024 and for the years ended December 31, 2023 and 2022. The Company’s separate financial statements as of March 31, 2024 and December 31, 2023 and for the three months ended March 31, 2024 and 2023, which are prepared in accordance with K-IFRS, are attached hereto.

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2. Dividends and Others

Omitted in quarterly reports in accordance with applicable Korean disclosure rules. For more information, please refer to the Company’s annual business report for the year ended December 31, 2023.

3. Use of Direct Financing

[SK Telecom]

[SK Broadband]

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4. Other Matters Related to Financial Information

Not applicable.

The Company establishes loss allowances based on the likelihood of recoverability of trade and other receivables based on their aging at the end of the period and past customer default experience for the past three years. With respect to trade receivables relating to wireless telecommunications services, the Company considers the likelihood of recovery based on past customer default experience and the length of default in connection with the type of default (e.g., whether the customer’s service has been terminated or is continued). Consistent with customary practice, the Company writes off trade and other receivables for which the prescription period has passed or that are determined to be impossible or economically too costly to collect, including receivables that are less than Won 200,000 and more than six months overdue and receivables that have been determined to be the subject of identity theft.

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The Company holds handsets, ICT equipment for offline sales, etc. in inventory. The Company conducts physical due diligence of its inventories with external auditors at the end of each year.

See Note 29 of the notes to the Company’s interim consolidated financial statements attached hereto for more information.

[SK Telecom]

The following are key terms and conditions of bonds issued by the Company. The compliance status is as of the date of the latest financial statements including the audit opinion of the independent auditor applicable to the determination of compliance status, except for the compliance status of the restriction on changes of ownership structure, which is as of the end of the reporting period.

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